Certain applications like to defer the decision to use a particular module
till runtime. This is possible in perl, and is a useful trick in
situations where the type of data is not known at compile time and the
application doesn't wish to pre-compile modules to handle all types of
data it can work with. Loading modules at runtime can also provide
flexible interfaces for perl modules. Modules can let the programmer
decide what modules will be used by it instead of hard-coding their names.
